Sheet receiving sorting machines useful for random distribution of sheets supplied from a copying or printing machine to a set of trays are generally complicated devices involving mechanisms for driving a sheet infeed system from tray to tray and/or costly due to the provision of gating devices for randomly removing sheets from a sheet transport system for carrying incoming sheets to selected trays. Such gate type sorters or mailboxes are usually fairly large, depending upon the number of trays and the nature of the sheet transporting systems.
Also moving infeed sorting devices associated with fixed trays sometimes impede the output speed of the host machine in order to appropriately transport successive sheets or designated selected trays when the space or gap between sheets or documents is small, and, in addition, such devices may be subject to sheet jamming in the distribution system for directing sheets to the appropriate trays.